Surgery in a Patient with Liver Disease


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Surgery is often needed in patients with concurrent liver disease. The multiple physiological roles of the liver
places these patients at an increased risk of morbidity and mortality. Diseases necessitating surgery like gallstones
and hernia are more common in patients with cirrhosis

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Surgery in a Patient with Liver Disease

  1. 1. Review Article JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGY Surgery in a Patient with Liver Disease Rakesh Rai*, Sanjay Nagral**, Aabha Nagraly *Department of HPB Surgery and Liver Transplantation, Fortis Hospital, Mulund, **Department of Surgical Gastroenterology, Jaslok Hospital, and yDepartment of Gastroenterology, Jaslok Hospital, Mumbai, India Surgery is often needed in patients with concurrent liver disease. The multiple physiological roles of the liver places these patients at an increased risk of morbidity and mortality. Diseases necessitating surgery like gall- stones and hernia are more common in patients with cirrhosis. Assessment of severity of liver dysfunction before surgery is important and the risk benefit of the procedure needs to be carefully assessed. The disease severity may vary from mild transaminase rise to decompensated cirrhosis. Surgery should be avoided if possible in the emer- gency setting, in the setting of acute and alcoholic hepatitis, in a patient of cirrhosis who is child class C or has a MELD score more than 15 or any patient with significant extrahepatic organ dysfunction. In this subset of pa- tients, all possible means to manage these patients conservatively should be attempted. Modified Child–Pugh scores and model for end-stage liver disease (MELD) scores can predict mortality after surgery fairly reliably in- cluding nonhepatic abdominal surgery. Pre-operative optimization would include control of ascites, correction of electrolyte imbalance, improving renal dysfunction, cardiorespiratory assessment, and correction of coagula- tion. Tests of global hemostasis like thromboelastography and thrombin generation time may be more predictive of the risk of bleeding compared with the conventional tests of coagulation in patients with cirrhosis. Correction of international normalized ratio with fresh frozen plasma does not necessarily mean reduction of bleeding risk and may increase the risk of volume overload and lung injury. International normalized ratio liver may better reflect the coagulation status. Recombinant factor VIIa in patients with cirrhosis needing surgery needs further study. Intra-operatively, safe anesthetic agents like isoflurane and propofol with avoidance of hypotension are advised. In general, nonsteroidal anti-inflammatory drug (NSAIDs) and benzodiazepines should not be used. Intra-abdominal surgery in a patient with cirrhosis becomes more challenging in the presence of ascites, portalSurgery hypertension, and hepatomegaly. Uncontrolled hemorrhage due to coagulopathy and portal hypertension, sepsis, renal dysfunction, and worsening of liver failure contribute to the morbidity and mortality in these patients. Steps to reduce ascitic leaks and infections need to be taken. Any patient with cirrhosis undergoing major surgery should be referred to a specialist center with experience in managing liver disease. ( J CLIN EXP HEPATOL 2012;2:238–246) T he incidence of liver disease in India is on the rise.1 specialties to be called upon to evaluate and reduce surgical The number of surgical procedures performed in- risk in a patient with deranged liver profile. cluding major operations is also increasing. There- In a patient being evaluated for surgery, liver disease fore, it is not uncommon for clinicians from various needs to be ruled out if there is a high-risk history like reg- ular, long-term alcohol consumption, blood transfusions, tattooing, IV drug abuse, and family history of liver disease. Keywords: Anesthesia, Child–Pugh score, cirrhosis, coagulopathy, hepatic Clinical suspicion of liver disease should arise in any pa- Received: 17.2.2012; Accepted: 15.5.2012; Available online: 20.8.2012 tient with palmar erythema, enlarged parotid glands, spi- Address for correspondence: Aabha Nagral, Department of Gastroenterology, der naevi, edema feet, gynecomastia and testicular Jaslok Hospital, 7, Snehasagar, Prabhanagar, Prabhadevi, Mumbai - 400025, India. atrophy in men or breast atrophy in women. The spectrum E-mail: of liver dysfunction in a surgical patient could range from Abbreviations: ABG: arterial blood gas; ASA: American Society of Anesthe- an incidental finding of mildly raised liver enzymes to se- siologists; BNP: brain natriuretic peptide; COPD: chronic obstructive pul- vere dysfunction as seen in a patient with acute liver failure monary disease; CTP: Child–Turcotte–Pugh; CVP: central venous or decompensated cirrhosis. In severe dysfunction, poten- pressure; FDP: fibrin degradation products; FFP: fresh frozen plasma; HPS: hepatopulmonary syndrome; ICG: indocyanine green; ICU: inten- tially every organ system may be affected.2 sive care unit; INR: international normalized ratio; MELD: model for In this review, we will discuss issues related to nonhe- end-stage liver disease; NSAID: nonsteroidal anti-inflammatory drug; patic surgery in a patient with liver disease. Assessment PICD: paracentesis-induced circulatory dysfunction; PT: prothrombin of risk especially in surgical conditions commonly encoun- time; PTT: partial thromboplastin time; SBP: spontaneous bacterial peri- tered in patients with cirrhosis, pre-operative optimization, tonitis; TEG: thromboelastogram; TIPS: transjugular intrahepatic porto- systemic shunt intra-operative, and post-operative precautions are elabo- rated. © 2012, INASL Journal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 238–246
  2. 2. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGYASSESSING OPERATIVE RISK the Mayo Clinic involving 772 patients with cirrhosisThe risk of surgery in a patient with liver disease depends who underwent major nonhepatic surgery, multivariableon various factors such as etiology and severity of the liver analysis revealed that MELD score, American Society ofdisease and the type of surgery. In a lifesaving procedure in Anesthesiologists (ASA) class, and age predicted mortalityan emergency, the assessment of risk is less relevant. In post-operatively. Thirty-day mortality was 5.7% in thoseplanned surgery, any degree of clinically evident liver dys- with MELD score of less than 8 compared with morefunction should be investigated thoroughly and optimiza- than 50% in those with MELD scores more than 20.9 Fur-tion of the patients medical condition and alternative ther, Hanje and Patel have suggested that patients withapproaches should be considered. The overall risk will MELD score of 10 or less can undergo elective surgery. Inalso need to take the urgency of surgery and other co- patients with MELD score of 10–15, elective surgery shouldexisting medical illnesses into account. be performed with caution and pre-operative optimization. On the other hand, in patients with MELD score of >15,Acute Liver Disease surgery should be avoided.10A patient with acute hepatitis of any cause has a poor Other Risk Factors for Morbidity and Mortalityoutcome following surgery. Friedman in an analysis of risk in Cirrhosisfactors affecting surgical outcome in patients with liver dis-ease identified acute hepatitis as an independent risk factor Ziser and Plevak11 reviewed 733 patients with cirrhosisand suggested that it should be considered a contraindica- who underwent surgical procedures (except liver trans-tion for elective surgery.3 Major elective surgery for a patient plantation) at the Mayo Clinic over an 11-year period.with suspected acute hepatitis E, for example, should be de- The mortality rate within 30 days of surgery was 11.6%.ferred until the patient has recovered, barring some compel- Long-term follow-up showed that most deaths occurredling reason for urgency such as a perforated viscus. within the first few months after surgery, when many pa- tients succumbed to pneumonia or renal insufficiency.Chronic Liver Disease Table 1 lists the factors that were found by multivariate analysis to be independently predictive of peri-operativeIn patients with chronic liver disease (CLD), outcomes cor- Surgery complications and of post-operative mortality. Thoughrelate with the underlying hepatocellular function. There this study did not look at MELD scores as it was publishedare two commonly used scoring systems for patients with prior to the popularity of the MELD scoring system, itliver dysfunction. The Child–Turcotte–Pugh (CTP)4 has been used for de-cades to assess the severity of liver disease. The score can be Table 1 Factors independently predictive of complications andcalculated at the bedside and its familiarity has made the mortality in patients with cirrhosis undergoing surgery.11system withstand the test of time. Multiple studies have Predictors of complications Predictors of mortalityshown its independent prognostic value across varied clin- Child–Pugh class B or C Male genderical settings both medical and surgical.5 Patients with class Ascites Child–Pugh class B or CC CTP score are not suitable candidates for major electivesurgery. The main weakness of the CTP score stems from Etiology of cirrhosis other than PBC Ascitesthe subjective measurement of ascites and encephalopathy. Elevated creatinine Etiology of cirrhosis other than Malinchoc et al developed a model for end-stage liver PBCdisease (MELD) score to predict survival in patients who Pre-operative infection Pre-operative infectionhad undergone transjugular intrahepatic portosystemic COPD ASA physical status 4–5shunt (TIPS).6 This statistical model predicted survival Pre-operative upper GI bleeding Respiratory surgeryand identified those patients whose liver-related post-TIPS mortality is 3 months or less. The MELD score is cal- Invasiveness of surgical procedureculated from the objective values of serum bilirubin, serum Intra-operative hypotensioncreatinine, and international normalized ratio (INR). The ASA physical status 4–5MELD score has been evaluated in multiple studies and The cumulative effect of these risk factors increased the probability ofhas proved to be effective in predicting surgical mortality developing a peri-operative complication is as follows:in cirrhosis.7 Befeler et al8 performed a retrospective study C 9.3% risk of complications with 1 risk factor.of 53 patients with cirrhosis undergoing abdominal sur- C 14.5% risk with 2 factors.gery, and concluded that the MELD provided a more accu- C 33.5% risk with 3 factors. C 63% risk with 4 or 5 factors.rate prediction of patient outcomes than the CTP scores. C 73.3% risk with 6 factors.Although this study was small, it showed the superiority C 100% risk with 7 or 8 factors.of MELD over CTP in predicting mortality in cirrhotic ASA: American Society of Anesthesiologists; COPD: chronic obstructivepatients undergoing surgery. In a more recent study from pulmonary disease; GI: gastrointestinal; PBC: primary biliary cirrhosis.Journal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 238–246 239
  3. 3. SURGERY IN A PATIENT WITH LIVER DISEASE RAI ET AL quantified the risk of surgical procedure with several other done pre-operatively for the gallstones. Marginally low se- parameters. rum albumin and platelet counts on blood tests and pres- ence of an enlarged caudate lobe or a dilated portal vein or Specific Disease-related Issues an enlarged spleen on ultrasound should alert the surgeon Alcohol to the likely presence of a CLD. Abstinence prior to elective surgery in those with history of Herniae excessive alcohol consumption needs to be advised to avoid Incidence of umbilical and inguinal hernias is higher alcohol withdrawal in the peri-operative period, even in the in patients with cirrhosis due to increased intra- absence of significant liver disease. These patients also have abdominal pressure secondary to ascites. Umbilical her- a higher risk of hepatotoxicity from drugs such as parace- nia can get complicated and lead to leakage, ulceration, tamol. rupture, and incarceration. These complications can Autoimmune Liver Disease lead to high mortality after emergency surgery. There- fore, an umbilical hernia should be repaired electively Patients with autoimmune liver disease are often on ste- in cirrhotics before they develop complications. However, roids or have been on steroids in the past. This fact needs the control of ascites before and/or after repair is neces- to be borne in mind with an increase in the steroid dose to sary. An attempt should be made to achieve this with di- cover the ‘stressful’ peri-operative period. uretics and paracentesis. Portal decompression by TIPS if Wilson Disease feasible allows better control of ascites. It has been ob- D-Penicillamine is the chelating agent used for treatment of served that with a sudden resolution of ascites, the chan- Wilson disease and it interferes with wound healing. In ces of obstruction of an umbilical hernia are higher as elective surgery, the dose of the drug needs to be reduced the sac which was preferentially occupied by the ascitic pre-operatively and the reduced dose continued for a few fluid can now accommodate the bowel. Therefore, the re- weeks after the surgery until the wound has healed com- pair should be carried out soon after the TIPS. These pa- pletely. tients should be managed in a tertiary center where facilities and experience to manage these patients areSurgery Risk Assessment in Commonly Performed available.16 Inguinal hernia on the other hand has a lower risk of Operations in Patients with Liver Disease complications and a higher risk of recurrence after surgery. Gall Stones Hence, elective surgical repair of an inguinal hernia is not Patients with cirrhosis are at increased risk of developing recommended in patients with cirrhosis. gall stone disease compared with noncirrhotic population. The prevalence of gall stone disease in cirrhosis can be up Cellulitis to 29%.12 The odds ratio for peri-operative mortality in pa- Cirrhosis leads to immunodeficiency and these patients are tients with liver disease who undergo cholecystectomy is at increased risk of infections.17 Besides, trauma to the 8.47.13 Perkins et al confirmed that a MELD score greater edematous lower limb predisposes to infections and pre- to or equal to 8 predicts an increased risk of post-operative vents early healing compared with those without edema. complications in open cholecystectomy.14 In a patient with Although spontaneous bacterial peritonitis (SBP) is a com- compensated cirrhosis and no significant portal hyperten- mon complication in a more recent series, cellulitis was de- sion, laparoscopic cholecystectomy can be safely per- tected in 19% of patients hospitalized with decompensated formed.13 Forty-four studies including a meta-analysis of cirrhosis while SBP was presented in only 4% patients. three randomized controlled studies comparing open Most common organisms causing bacterial skin infection with laparoscopic cholecystectomy were analyzed. Laparo- in noncirrhotic population are gram-positive pathogens scopic cholecystectomy was associated with a lower opera- (mainly group A streptococci and Staphylococcus aureus), tive time, reduced complication rates, and a shorter and infrequently caused due to gram-negative organisms. hospital stay.15 In a patient with decompensated cirrhosis, Skin infections in case of cirrhosis are most commonly cholecystectomy should be avoided and if there is a dire due to gram-negative organisms.18,19 Thus, it is important need for intervention, a cholecystostomy may be per- to choose an antibiotic with gram-negative coverage in formed. a cellulitis patient till culture results are available. Cellulitis It is not unusual to diagnose cirrhosis for the first time should be treated early due to increased risk of septic when a laparoscope is introduced for the removal of gall- complications in cirrhotics. stones. The procedure is either abandoned or completed with increased risk of post-operative complications. Ide- Morbid Obesity Surgery ally, this situation should not arise and the cirrhosis Morbidly obese patients often have associated non- should be picked up on blood tests or ultrasound imaging alcoholic steatohepatitis (NASH). About three quarters of 240 © 2012, INASL
  4. 4. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGYbariatric surgery patients have liver steatosis, a quarter have PRE-OPERATIVE OPTIMIZATIONfibrosis and 1–2% of patients will have cirrhosis as an un- All patients with clinically suspected liver disease should beexpected finding on the table.20,21 In a recent study by assessed for evidence of decompensation in the form ofMosko et al, patients without cirrhosis undergoing jaundice, coagulopathy, ascites, renal dysfunction, electro-bariatric procedures had lower mortality rates than those lyte abnormalities, and encephalopathy. Factors known towith compensated and decompensated cirrhosis.22 exacerbate hepatic encephalopathy should be corrected Thus, bariatric surgery in patients with cirrhosis could though there is no evidence that prophylactic therapybe carried out cautiously when cirrhosis is well compen- can prevent encephalopathy after surgery. Patients withsated, but in patients with decompensated cirrhosis or known varices should receive the appropriate prophylaxiswith significant portal hypertension, bariatric surgery and fluid overload should be avoided post-operatively.should be deferred. These patients are candidates for liver The laboratory tests to assess these abnormalities alsotransplantation. Transjugular intrahepatic portosystemic provide parameters necessary for calculation of the CTPshunt procedure has been described prior to the trans- and MELD scores. In patients with liver disease undergo-plant followed by a bariatric procedure like laparoscopic ing liver resection surgery, it is important to assess the he-banding to reduce the risk of portal hypertension-related patic reserve. There are multiple tests to assess the hepaticbleeding. reserve26 but one which has been studied in detail is indoc-Cardiac Surgery yanine green retention rate at 15 min (ICGR-15).27 These are less relevant in patients undergoing nonhepatic sur-Coronary artery bypass carries a higher risk in patients gery. Computed tomography (CT) volumetry, assesseswith cirrhosis. One of the largest series included 44 the residual volume and function of the remaining liver.patients of which 7 patients died due to hepatic decompen- Along with the assessment of the severity of liver dys-sation.23 A number of risk factors for hepatic decompensa- function, it is important in the pre-operative work-up totion following cardiac surgery were identified including optimize the wide range of physiological derangementsCTP score, total time on cardiac bypass, and need of caused by declining liver function in patients withperi-operative pressor support.23 In a recent publication, cirrhosis.Modi et al reviewed the data on patients with cirrhosis un- Surgerydergoing coronary artery bypass surgery and concludedthat cardiac surgery could be offered to patients with Cardiovascular FunctionChild–Pugh A and a low MELD score with mild increase Irrespective of the etiology, patients with cirrhosis havein the risk of mortality. However, for patients with more a hyperkinetic and hyperdynamic circulation with tachy-advanced cirrhosis, the risk of mortality is un-acceptably cardia, low systemic blood pressure, and low left ventricu-high. Cardiopulmonary bypass may increase the risk of lar after load associated with splanchnic vasodilatation.bleeding by inducing fibrinolysis, platelet dysfunction, Peri-operative vasoconstrictor infusion may be necessaryand hypocalcemia. Revascularization without the use of to prevent further hypotension. In addition to alcohol,cardiopulmonary bypass may be a lower risk but in these cirrhosis per se is associated with a cardiomyopathydecompensated patients long-term survival is significantly known as cirrhotic cardiomyopathy which is characterizedpoor and health status is compromised even well after car- by blunted ventricular systolic and diastolic contractilediac surgery.24 responses to physical and pharmacological stress.28 The systolic dysfunction gets manifests during stressful proce- dures such as TIPS. It has also been implicated in renal dys-CONTRAINDICATIONS FOR SURGERY function in the end-stage liver disease. The QT interval is prolonged in 50% of patients with cirrhosis and may man-Friedman13 proposed the following list of contraindica- ifest as a rhythmic disturbance which may be treated withtions to elective surgery in patients with liver disease: beta-blockers. Also, drugs which prolong QT interval need1. Acute viral hepatitis. to be used with caution. Routine cardiovascular testing is2. Alcoholic hepatitis. In a retrospective series of patients advisable in patients with cirrhosis with an electrocardio- with alcoholic hepatitis, the mortality rate was 58% gram to detect a prolonged QT interval, which has been among the 12 patients who underwent open liver bi- shown to significantly correlate with the severity of liver opsy, compared with 10% among the 39 who underwent disease, elevated brain natriuretic peptide (BNP) level, percutaneous liver biopsy.25 and decreased survival. A 2D echo should also be done to3. Acute liver failure. identify systolic and diastolic dysfunction. Cirrhotic car-4. Acute renal failure. diomyopathy is best picked up by dobutamine stress5. Severe coagulopathy. echo.29 The prevalence of coronary artery disease is high6. Hypoxemia. in cirrhotic population where diabetes, alcohol abuse,7. Cardiomyopathy. and smoking are common. Pulmonary artery hypertensionJournal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 238–246 241
  5. 5. SURGERY IN A PATIENT WITH LIVER DISEASE RAI ET AL defined as the mean pulmonary artery pressure >25 mmHg PICD is reduced by pre-emptive administration of intrave- is seen in 5% of patients with cirrhosis.30 It increases the nous albumin at 6–8 g/L of ascites removed.39 Large vol- risk of surgery, even in those with mild pulmonary hyper- ume ascites will benefit from pre-operative paracentesis, tension and therefore the indication for surgery needs to be diuretic therapy, and stringent limitation of sodium intake carefully evaluated. to 2 g/day to minimize reaccumulation of the ascitic fluid. In a patient with refractory ascites planned for surgery, Respiratory Function TIPS may be used to control the ascites if the patient Up to 40% of the patients with cirrhosis are hypoxic. does not have any contraindication for TIPS and has Causes of hypoxia can be related to pleural effusion, tense a MELD score <18.40 This has also shown to decrease the ascites, or hepatopulmonary syndrome (HPS).30 The cause portal hypertension to allow abdominal surgery to take of HPS is shunting of blood in pulmonary vascular bed due place.41,42 to dilatation of the pulmonary precapillary arterioles. In HPS, physical findings may reveal digital clubbing and cy- Hemostasis anosis. During pre-operative work-up of a patient with cir- Coagulation is a complex interaction of procoagulation rhosis, a measurement of arterial blood gas (ABG) should and anticoagulation pathways and the fibrinolytic sys- be done as a screening tool. A PaO2 of <80 mmHg suggests tem.43 Majority of plasma clotting factors and components significant hypoxemia and HPS should be ruled out by of the fibrinolytic and anticoagulant pathways are synthe- contrast echocardiography.31 There is no therapy which sized in the liver. will improve oxygenation in case of HPS and only treat- Therefore, patients with liver disease have a risk of ment is liver transplantation. As it carries a poor prognosis, bleeding as well as thrombosis. Infections, endogenous any patient with HPS requiring surgery other than liver heparinoids, and renal failure can also affect coagulation transplant should be explained the high-risk and if possi- in patients with decompensated liver cirrhosis.44 ble should be treated by nonsurgical interventions.32 Other Bleeding is also associated with thrombocytopenia sec- causes of hypoxia-like pleural effusion and ascites need to ondary to hypersplenism, thrombopoietein deficiency, be aggressively treated in the pre-operative period to opti- (myelosuppression due to hepatitis C, folate deficiency, mize the patients respiratory status before surgery. Vari-Surgery and ethanol toxicity), autoantibodies and low-grade dis- ous indices like the Goldman cardiac index have been seminated intravascular coagulation (DIC).45 used to assess the post-operative risk of cardiac and pulmo- Conventional coagulation tests include clotting time, nary complications.33 PT, INR, and activated partial thromboplastin time. These measure only part of the process of thrombin generation. Renal Dysfunction and Ascites Further, it is not certain if INR reflects the true risk of In patients with cirrhosis, renal blood flow gets compro- bleeding in patient with liver disease. Since fibrinogen mised due to splanchnic vasodilatation and glomerular fil- plays a role in the last step toward fibrin clot formation tration rate can be low in spite of a normal serum in the clotting cascade, serum fibrinogen and tests of fibri- creatinine due to poor muscle mass.34 Pre-operative fasting nolysis like clot lysis time may also be included. and intra-operative fluid loss if not corrected appropriately Tests for global evaluation of coagulation-like throm- can lead to functional renal failure in these patients. In pa- bin generation time, and thromboelastography,46 and tients with cirrhosis, there is a substantial risk for develop- INR calibrated for cirrhosis (INR liver)47 may be more ac- ing contrast-induced nephropathy; hence, any radiological curate in prediction of bleeding complications. Thrombin examination which needs contrast should be avoided im- formation is globally measured by using a thrombin gener- mediately before surgery.35 If contrast is necessary, then ation assay modified by the addition of thrombomodulin, the patient needs to be well hydrated and low-volume and hence it assesses both plasma level of coagulation fac- non-ionic iso-osmolar agent should be used.36 Nonsteroi- tors and also coagulation inhibitors in patients with liver dal anti-inflammatory drugs (NSAIDs) should be avoided disease.48 Thromboelastography measures clot formation, as they may lead to renal dysfunction37 as well as increase clot strength, and clot dissolution but does not measure the risk of variceal bleeding in cirrhosis.38 Among the anti- vascular tone. It evaluates global hemostasis, though there biotics, aminoglycosides should also be avoided. have been conflicting reports on its reliability in different Ascites is associated with increased incidence of infec- studies.49 It has been shown to be a significantly better pre- tions, renal failure, and worse long-term outcome. Patients dictor of post-operative bleeding than the coagulation pro- with ascites present a significant challenge for abdominal file.50 The INR liver is a modification of the standard INR surgery. The sudden loss of large volume ascitic fluid dur- where PT is calibrated using plasma from patients with cir- ing surgery can lead to paracentesis-induced circulatory rhosis instead of vitamin K antagonists and is thought to dysfunction (PICD), which is due to the activation of re- resolve variability of INR in these patients. However, these nin–angiotensin–aldosterone system. The incidence of tests have not been prospectively evaluated in patients with 242 © 2012, INASL
  6. 6. JOURNAL OF CLINICAL AND EXPERIMENTAL HEPATOLOGYliver disease.47,51 Recently, Tripodi et al described a simple Desmopressin: Administration of 1-deamino-8-D-argi-laboratory method which evaluates protein C deficiency nine vasopressin (DDAVP)—Desmopressin, an analog ofwhich could promote clotting in patients with cirrhosis. anti-diuretic hormone vasopressin—has been used forThis test is a standardizable laboratory test which may hemostasis in conditions associated with platelet dysfunc-determine the relative risk of clotting vs bleeding in tion like uremia. It shortens the bleeding time but notpatients with cirrhosis.52 much benefit has been recorded in clinical trials. A recent A precise platelet count rather than ‘adequacy’ is neces- study found intranasal desmopressin in a dose ofsary. Bleeding time would give an idea of platelet function 300 mcg to be as effective as transfusion of blood productsthough several more sensitive tests for platelet function in achieving hemostasis in cirrhotic patients with moder-have been described. ate coagulopathy undergoing dental extraction.56 We would currently recommend a CBC, bleeding time, Antifibrinolytics: A hyperfibrinolytic state should be con-PT, PTT, and fibrinogen as minimum tests in all patients sidered in the setting of delayed bleeding following a pro-with cirrhosis needing surgery. However, efforts should cedure or intractable oozing from a wound. Saliva andbe made to make thrombin generation assay and TEG ascites have increased fibrinolytic properties, which isavailable. perhaps the rationale of using anti-fibrinolytics in pa-Management of Peri-operative Bleeding in Patients tients with cirrhosis and intra-peritoneal or dental bleed-with Cirrhosis ing. Tranexamic acid has been used administered with a 10 mg/kg loading dose and repeated 3–4/day for a totalVitamin K: Although coagulopathy is usually due to poor of 2–8 days.57hepatic function, cholestasis and concomitant poor nutri-tion or malabsorption due to gut edema could also lead to Recombinant factor VIIa: In severe bleeding during sur-vitamin K deficiency. Vitamin K injection is given prefera- gery, recombinant factor VIIa in the dose of 40 mcg/kgbly IV in dose of 10 mg for 3 days in patients with decom- may be effective in the correction of coagulopathy and re-pensated cirrhosis undergoing surgery. Oral vitamin K has ducing blood product requirements. Its effect is transientno role. and needs repeated dosing and is extremely expensive. Though, it corrects in vitro tests of coagulation, its benefit SurgeryFresh frozen plasma and cryoprecipitate: The short half- in patients with cirrhosis undergoing nonhepatic surgerylife of factor VII in fresh frozen plasma (FFP) (3–5 h) neces- has not been documented.58sitates administration of the FFP immediately before sur- Needless to mention, a major factor determining the ex-gery and at frequent intervals during surgery with tent of correction of coagulopathy during surgery shouldmonitoring of coagulation parameters.53 Fresh frozen be the surgeons assessment of the cause and severity ofplasma contains all coagulation factors, inhibitors of coag- the on-going bleeding. Other measures such as maintain-ulation, and fibrinolytic factors. The recommended dose of ing low central venous pressure (CVP) and reducing theFFP is 10–15 mL/kg, although the response in patients portal pressure during surgery are also helpful.with decompensated liver cirrhosis is unpredictable. Hypercoagulable state may also occur in cirrhosisBesides, correction of INR by FFP has not been shown to with risk of micro- and macrovascular thrombosis.59,60reduce the risk of bleeding. Also, FFP administration has Thrombotic complications in cirrhosis manifest usuallybeen associated with significant problems including vol- as deep vein thrombosis, pulmonary embolism, andume overload, exacerbation of portal hypertension, risk acute portal vein thrombosis. These can be carefully andof infections, and risk of transfusion-related acute lung safely treated with anticoagulants.51 Low-molecular-injury.54 Cryoprecipitate infusions are recommended for weight heparin has shown to be of benefit in preventingthose with serum fibrinogen <100 mg/dL in a dose of portal vein thrombosis in cirrhosis in a recent randomizedone bag of cryoprecipitate per 10 kg of body weight. This control study.61,62may be preferable to FFP as the volume required is much In a nutshell, hemostasis in patients with decompen-lower. sated liver disease is complex. Conventional tests forPlatelet transfusions: Thrombocytopenia of <50,000/mL coagulation have a poor predictability for bleeding orfor moderate risk and 100,000/mL for high-risk procedures thrombosis in these patients. Tests measuring global he-should be corrected by platelet transfusion, which is ideally mostasis including thromboelastogram (TEG) andgiven at the start of surgery and not before surgery.55 Plate- thrombin generation time seem to be more predictivelets are transfused in the dose of 1 unit per 10 kg of body of clotting problems and need to be validated in futureweight, which means 5–8 units of whole blood-derived studies. Similarly, newer interventions to correctpooled donor platelets or 1 unit of single donor platelet coagulation-like recombinant factor VIIa and antifibrino-for prophylaxis. Higher doses may be needed for patients lytics need to be tested in a prospective manner. Until wewith active bleeding. This is expected to raise the platelet have sufficient data, the conventional approach of par-count by approximately 30,000/mL. tially correcting abnormal coagulation peri-operativelyJournal of Clinical and Experimental Hepatology | September 2012 | Vol. 2 | No. 3 | 238–246 243
  7. 7. SURGERY IN A PATIENT WITH LIVER DISEASE RAI ET AL may be continued. However, this may not necessarily during prolonged procedures is necessary and a TEG in translate into clinically effective hemostasis. the operating room is a useful, quick adjunct. However, there is not much literature on the use of TEG in nonhe- Malnutrition patic surgery in patients with cirrhosis. Patients with CLD have protein calorie malnutrition and impaired glucose tolerance. Also, they are often deficient Anesthetic Management in fat-soluble vitamins (cholestatic disorders) or trace ele- Patients with liver disease are more likely than patients ments and vitamins like zinc, magnesium, copper, folate, without liver disease to have hepatic decompensation and B12. These deficiencies could delay wound healing with the use of anesthesia.3 and increase the risk of infections and complications. The decreased hepatic perfusion at baseline makes the About 80% of patients with cirrhosis suffer from malnu- cirrhotic liver more susceptible to hypoxemia and hypoten- trition.63 Serum albumin, prealbumin, and triglyceride sion in the operating room. At baseline, hepatic arterial levels are helpful to objectively quantify the patients nutri- and venous perfusion of the cirrhotic liver may be de- tional status, in addition to observing physical signs of ca- creased: portal blood flow is reduced as a result of portal chexia and wasting. Even in patient with childs class A, the hypertension, and arterial blood flow may be decreased be- prevalence of malnutrition can be as high as 25%.64 In the cause of impaired autoregulation. Anesthetic agents may pre-operative period, every effort should be made to im- reduce hepatic blood flow by 30–50%, and agents such as prove nutritional status before surgery. In January 2006, isoflurane, desflurane, sevoflurane, and propofol, which the European Society for Clinical Nutrition and cause less disturbance in hepatic arterial blood flow than Metabolism (ESPEN) issued specific guidelines on enteral other inhaled anesthetic agents, are preferred for patients nutrition in liver disease which can be easily applied in with liver disease.66 both inpatients and outpatients.65 The guidelines con- Myocardial depression and vasodilatation are common cluded that undernutrition adversely affects the prognosis to majority of anesthetic agents. These effects are of con- in cirrhosis and simple bedside methods such as anthro- cern since many patients with advanced liver disease pometry or subjective global assessment (SGA) are consid- already have a hyperdynamic circulation because of periph- ered adequate to identify patients at risk. eral vasodilatation. Spinal or epidural anesthetics may re-Surgery Several misconceptions related to diet in the setting of duce the mean arterial pressure, which is of concern for liver disease exist in India, aggravating the pre-existing similar reasons. Also, these routes are not preferred in malnutrition. A high protein diet up to 1–1.5 g/kg body those with coagulopathy or thrombocytopenia. Halo- weight with sodium restriction to 2 g in those with ascites thane, 20% of which is metabolized by the liver, is now un- is used. Usually, patients with liver disease have loss of ap- commonly used and should be avoided in those with liver petite; hence, feeding through a nasogastric tube should be disease.67 In contrast, enflurane is only 4% metabolized by considered. Branched-chain amino-acid-enriched formula the liver. Isoflurane, desflurane, and sevoflurane have only may be used as a source of protein in those with hepatic en- minimal hepatic metabolism (<0.2%), which makes them, cephalopathy. Placement of nasogastric or nasojejunal along with nitrous oxide, the best anesthetic choices for pa- tube for feeding in the presence of varices does not increase tients with liver disease. In general, propofol is preferred to the risk of bleeding. benzodiazepines as a narcotic. Among opioids, sufentanil and remifentanil are preferred68 and oxazepam is the pre- ferred sedative in liver insufficiency. INTRA-OPERATIVE MANAGEMENT The muscle relaxants, vecuronium and rocuronium, are Pre-operative risk reduction strategies such as paracentesis, metabolized exclusively by the liver and therefore treatment of coagulopathy, hypovolemia, respiratory and avoided.69 Atracurium and cisatracurium are metabolized renal dysfunction, and improving nutritional status independent of the liver and are preferred in patients should be employed and it is important for surgeons and with liver disease.68 anesthetists to be aware of the physiological changes caused by liver disease. Usually during any major surgery, arterial line and central venous line should be inserted to POST-OPERATIVE MONITORING monitor intravascular volume, frequent blood sampling, In patients with cirrhosis, liver failure is the most common and to administer vasoactive drugs if needed. cause of post-operative death.13 Depending upon the type Because of the portal hypertension and associated coa- of surgery and the severity of liver disease, it is important to gulopathy, patients can have excessive bleeding. Besides monitor for expected complications and to pre-emptively meticulous surgical technique, the use of coagulation take steps to prevent complications. In any patient with diathermy and energy sources like harmonic scalpel is child B or C cirrhosis who undergoes surgery under general preferred. Hemostatic continuous suturing should be anesthesia, it is important for the patient to be monitored preferred for suture lines. Monitoring of coagulopathy post-operatively in an ICU setting. These patients take 244 © 2012, INASL
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